Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
J Acquir Immune Defic Syndr. 2011 Oct 1;58(2):141-7. doi: 10.1097/QAI.0b013e31822866a2.
Enumeration of CD4+ T-lymphocytes is important in the management of HIV. However, standard laboratory systems based on flow cytometry are expensive, complicated, and thus unavailable to most resource-limited settings where a low-cost and fully automated point-of-care CD4 testing system is required. In attempts to address this issue, a study was conducted to validate the Alere PIMA point-of-care CD4 test.
Duplicate values of the absolute number of CD4+ T-lymphocytes in 203 HIV-infected blood samples obtained using the PIMA system were compared with the two predicate single-platform FACSCount and the dual-platform FACSCan (Becton Dickinson Biosciences).
The overall absolute CD4+ T-lymphocyte count obtained using the PIMA system correlated highly with the FACSCount (r = 0.957; mean bias, -54.2 cells/μL; limit of agreement, -190.9 to +82.5 cells/μL) and the FACSCan (r = 0.957; mean bias -44.0 cells/μL; limit of agreement, -179.7 to +91.6 cells/μL). Good correlation and low biases were also observed for samples with CD4+ T-lymphocyte count ranges of 0 to 200 and 0 to 350 cells/μL. Additionally, there was no significant difference in absolute CD4+ T-lymphocyte counts noted between the duplicate samples using the PIMA system.
This new point-of-care product is a simple and reliable system and should contribute significantly to the simplification of performing CD4 testing and thus increase access for patients in resource-limited settings. The inability to obtain values for the frequency (%) of CD4+ T-lymphocyte count is one limitation of the PIMA system, the addition of which would be of value for clinical staging or monitoring in HIV-infected pediatric patients.
CD4+T 淋巴细胞的计数在 HIV 的管理中非常重要。然而，基于流式细胞术的标准实验室系统既昂贵又复杂，因此无法在大多数资源有限的环境中使用，而这些环境需要一种低成本且完全自动化的即时护理 CD4 检测系统。为了解决这个问题，我们进行了一项研究来验证 Alere PIMA 即时护理 CD4 检测。
使用 PIMA 系统获得的 203 份 HIV 感染血液样本的 CD4+T 淋巴细胞绝对数的重复值与两种单平台 FACSCount 和双平台 FACSCan（Becton Dickinson Biosciences）进行了比较。
PIMA 系统获得的总体绝对 CD4+T 淋巴细胞计数与 FACSCount（r = 0.957；平均偏差，-54.2 个细胞/μL；一致性界限，-190.9 至 +82.5 个细胞/μL）和 FACSCan（r = 0.957；平均偏差-44.0 个细胞/μL；一致性界限，-179.7 至 +91.6 个细胞/μL）高度相关。在 CD4+T 淋巴细胞计数范围为 0 至 200 和 0 至 350 个细胞/μL 的样本中也观察到了良好的相关性和低偏差。此外，使用 PIMA 系统获得的重复样本之间的绝对 CD4+T 淋巴细胞计数没有显著差异。
这种新的即时护理产品是一种简单可靠的系统，应该会极大地简化 CD4 检测，从而增加资源有限环境中患者的获得机会。PIMA 系统无法获得 CD4+T 淋巴细胞计数频率（%）的值是其一个限制，添加这一功能对于 HIV 感染儿科患者的临床分期或监测将具有重要价值。
